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Laser Blast Makes Regular Light Bulbs Super-Efficient
guruevi writes with news that a process using an ultra-powerful laser can crank up the efficiency of everyday incandescent light bulbs. Using the same laser process covered several years ago, the tungsten filament has an array of nano- and micro-scale structures formed on the surface making the resulting light as bright as a 100-watt bulb while consuming less electricity than a 60-watt bulb and remaining much cheaper to produce. "The key to creating the super-filament is an ultra-brief, ultra-intense beam of light called a femtosecond laser pulse. The laser burst lasts only a few quadrillionths of a second. To get a grasp of that kind of speed, consider that a femtosecond is to a second what a second is to about 32 million years. During its brief burst, Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point. That intense blast forces the surface of the metal to form nanostructures and microstructures that dramatically alter how efficiently light can radiate from the filament."
Laser Blast Makes Regular Light Bulbs Super-Efficient
So that whole time in Star Wars, they were just trying to make each other Super-Efficient? That's a whole lot nicer than what I was led to believe was initially going on.
LASIK makes a lot more sense now too.
I'm learning!
My work here is dung.
So, considering they are as cheap to produce as normal lightbulbs, we can expect to see these on the shelves in...2050?
But it doesn't matter (at least to those of us in the USA), because in 2014 incandescent bulbs will be banned.
End of lesson. You may press the button.
Of only white LEDs were this efficient as well...oh wait...never mind.
Ezekiel 23:20
The technique has been used to make extremely efficient light-absorbing surfaces; but hadn't been applied to light-emitting surfaces until now. Since those are two sides of the same coin, I'd have expected somebody to try it much sooner(though, I'll admit, I didn't think of it).
On the plus side, greater efficiency in incandescents is always good(though I'd be quite interested to know how cheap laser treating filaments can possibly be). I predict that this thread will probably be infested by the "CCFLs are Evil!" brigade soon enough...
... and remaining much cheaper to produce.
... Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.
What?
Whale
Why not set an efficiency factor on a bulb(like cafe standards) instead of banning the different technologies?
Something I never understood.
Too bad we won't be able to buy Incandescents any more in a couple years.... :-(
http://www.formplusfunction.com/blog/2009/will-incandescent-bulbs-soon-be-outlawed/
unless they can get the new bulbs to 70% less power used.
The clock is ticking to 2014 (when 40watts are outlawed).
sorry for the link, didn't have time to find a reputable site...
Arguing with an engineer is like wrestling a pig in the mud. After a while, you realize the engineer enjoys it.
Too late: Compact fluorescent lamps require about 20W for the same light output as a 100W incadescent.
And live longer too.
Yes, their light used to look shitty, but these times are over now as well - if you don't buy the cheapest
there are, the light out of fluorescent bulbs is perfectly fine. And LED "bulbs" may soon be there too.
and it only takes 11 years of operating the more efficient bulb to compensate for the energy consumed during the laser burst
This is the might Slash. We can understand proper units.
Femto = 10^-15
"The price good men pay for indifference to public affairs is to be ruled by evil men." ~Plato (427-347 BC)
But long does the lamp last? It's easy to make an incandescent lamp more efficient. You just crank up the filament temp, but then your lifetime goes to pot. Lamps last 1000 hours because that's how frequently consumers are willing to unscrew and rescrew their bulbs.
No, that's just a mainstream news unit of measure. We now have football fields, libraries of congress (LOCs), swimming pools (for area?), and the entire power output of the north american energy grid.
"We returned the General to El Salvador, or maybe Guatemala, it's difficult to tell from 10,000 feet"
Perhaps it operates more efficiently, but it doesn't sound like it is so efficient to produce. Unless I'm misunderstanding or misrepresenting the verbiage from the summary.
You forgot that femtosecond part. The usage of the whole USA grid is for an incredibly tiny fraction of a second, 10^15 of a second. The USA grid is 4x10^15 watts. So really, if you want to translate it into a more sane energy understanding, its about four watts per bulb to do this.
This is my sig.
Oh, that's easy to answer. It's a tag. Makes it easy to spot where people have been bought to push certain agendas and fill pockets. Let me just ask you this: Do you think profit margins on old-school bulbs are a) smaller or b) larger than on more modern alternatives?
Whenever legislation is worded in such a way that it does not encourage competition to reach a certain goal, you can bet your cute fanny that the true goal of said legislation lies not in the stated goal but in the way as to get there.
That's basically why I'm for voting for politicians AFTER they've been in office. The outcome of said vote will decide how much pension the person gets for the work done. If abysmal enough, I'm all for incarceration.
Even if the luminous efficacy improves a 60 watt incandescent to that of a 100 watt bulb that still puts it around 29-30 lumens per watt, about 30% of a good fluorescent or LED light source.
This is a nice improvement for an inherently inefficient and quite dated technology, but hardly but hardly "super-efficient" in the larger sense of overall luminous efficacy.
There's an app for that.
You screwed up your units, there. (watts)x(seconds) = joules.
You also forgot the negative on the exponent, but I'll forgive you for that...
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Let's do the math. From that fount of knowledge that is wikipedia, the US grid is about 4 thousand terawatts. That's 4*10^15 W.
So say we want over 4 times that, like 20*10^15 W to give 4 times the power of the US grid.
Power is energy divided by time. 1 femtosecond is 10^(-15) sec.
Let energy in joules be E, power in watts be P and time in seconds be T, then
E = P*T
So the energy of power 20*10^15 W times times time 10^(-15) is just 20 Joules.
Say it takes 1 sec to pump the laser, that's an average power of 20W. Of course the laser pumping
isn't 100% efficient, and 1 sec might not be the exact right time, it's still feasible. It's only the equivalent
energy of having the light bulb lit for a few seconds.
Yoghurt
So does this mean every evil genius lair is now only complete with sharks with freekin' light bulbs on their heads?
--- Users are like bacteria -> Each one causing a thousand tiny crises until the host finally gives up and dies.
You mean like they mandated emission standards instead of requiring every car to be built with a catalytic converter? Who would be silly enough to pay for lobbying for a law that doesn't favor their own industry while penalizing their competitors?
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Energy and Power are not the same. Specifically, Power is Energy divided by Time. W = E/t
Based on just the US, which for the sake of half-arsed napkin engineering on /. I will double to get total energy usage for North America in 2005, we're talking about 58000 TWh / 8760 h = 6.621 TW average power output.
Thus the laser pulse itself uses 6.621E12 W * 1E-12 J = 6.621 J.
The "efficient" lightbulb saves 40W. 6.621 J / 40 W = 0.165 s.
So it takes less than a second to recover the energy used by the laser. I'm sure the laser system itself uses more power than what is just in the beam, but the point is, ridiculous amounts of power in ridiculously short amounts of time results in quite rational and manageable power levels.
The enemies of Democracy are
FYI the best Flourcent bulb is 100 lm/Watt (CFL is 60-72) while the best white LED is 131 lm/Watt (over 150 lm/Watt for some other colors.) http://en.wikipedia.org/wiki/Compact_fluorescent_lamp#Energy_efficiency
so while currently most CFL beat most LED in efficiency, inherently it looks like LED has a better future. Especially with LED lights having a longer (best case) lifetime, and being instant on to full power, and no high voltages present.
The LED at home being a new trend, with in-efficient transformers, and cheap production units likely causing damage to their reputation. Much like Fluorescent is still trying to get over the poor initial products reputation (with odd colors, poor life, and several minutes of power up, with constantly buzzing transformers, and odd harmonics with monitors, video cameras, and TV's.)
Conservation is a red herring: population growth will outstrip any resulting savings. Instead, we should focus on generating energy sustainably. We can do that today with a combination of wind, hydroelectric, and nuclear power.
Conservation almost always reduces our quality of life. Why should we do that when we have the technology to not only save the environment, but improve our lives as well? We should be encouraging people to use more energy when that power makes life easier. By all rights, electricity should be cheap and plentiful.
I can't help but wonder whether conservation advocates feel guilt over civilization itself. I certainly don't. There's no shame in using technology to make our lives better.
Dunno if this is gonna happen yet, or not, but I've seen articles about the use of oLed sheets as light sources - instead of being a 'bulb' in the usual sense, think more like those ceiling mounted fluorescent light fixtures with diffusers so common in schools, office buildings, and retail. Or, think of a computer monitor that is all white (although, the light need not be pure white - could be offwhite colors - could even change the color when you want, maybe), but brighter. They also say that OLEDs will become thin and flexible, so you could take your OLED 'film' and wrap it around a curved surface or something.
So, you could have lighting that looks like a sort of 'standard' table-lamp with a lampshade - except the 'lampshade' is actually the OLED 'film', giving off light directly into the room, with no bulb inside the lampshade.
That's still a number of years into the future, if it ever happens. OLEDs have to become many times cheaper than they are now before that'll happen.
How many lightbulbs would they need to convert from 100W to 60W usage (over time) to equal the energy cost of 1 femto second laser blast
Dunno, but my guess is that for each lightbulb, it will take at least 3 Slashdotters to screw it in. One to hold the ladder, one to screw it in, and one to explain the significance of a femtosecond.
That's not including the dozen or so other Slashdotters who will want to attend and debate the relative merits of CFLs and LEDs, another dozen who insist they're wrong, a few older Slashdotters who moan about the old lightbulb working just fine, and one guy standing in a corner mumbling something about a government conspiracy while rolling out tinfoil to fashion a head covering.
Apples and oranges. You're talking about two different problems as if they're the same problem.
The local problem with CFL's (they contain a trace of mercury) is outbalanced by the central problem of coal-burning releasing even more mercury.
The local problem with an internal combustion engine (it constantly pumps many pollutants into the environment) is not outbalanced by the central problem of power plant pollution.
These two statements would only be in contradiction if the polluting effect of the mercury in a CFL were on the same order of magnitude as the polluting effect of an internal combustion engine. It's not even close.
60W-equivalent (actual rating 11W) fluorescents are frequently on offer at ten for a quid: I've seen that deal twice in different stores in the last few months. Given how long they last, you could get yourself a lifetime's supply for the price of a decent round of drinks.
Real Daleks don't climb stairs - they level the building.
Watts is a measurement of joules per second, so if you multiple power by time (as in applying 4x10^15 Watts for 10^-15 seconds) you get 4 joules.
The rest goes to feed the sharks.
Patents Drive Free Software as Hurricanes Drive Construction Industry
Too late. Incandescent light bulbs are illegal soon. Who needs technology when we have laws?
Hold on a sec. They're...
I'm having a little trouble with imagining how it could be efficient to do that for every lightbulb sold.
I remember reading somewhere that incandescent bulbs are made somewhere in America -- Tennessee? Whereas the great majority of CFLs come from China. If incandescent bulbs can be made significantly more efficient, and they're made locally, it sounds like a win-win to me.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
a longer description of Power Factor:
http://www.ee.bgu.ac.il/~instlab/Experiments/05_FlurLamp/PowerFactor1.pdf
A lightbulb works because the filiment gets really hot and glows with blackbody radiation. All of the electric power that goes into the bulb is radiated. So in some sense, the incandecent bulb is already 100% effecient. the only problem is that most of the radiated energy is at infrared frequencies and doesn't do anything to light the room for human eyes. If you increase the emmisivity of the filiment to 100%, it is not obvious that you increase the effeciency of the bulb one iota. In fact, I would guess that the effeciency of the bulb goes down, since the filiment temperature will go down (since you radiate more power at a given temperature) and more of the radiation will be in the IR. Now, if he can change the surface of the filiment so the emmisivity is very high in the visable but very low in the IR, then and only then will he be onto something. -Rob (and yes, I am in fact a physicist)
Me and Steve Jobs shove iPhones up each other's asses for fun.
Steve Jobs and I.
Fnord.